1. Field of the Invention
This invention pertains to insulating apparatus, and more particularly to conveniently carryable personal insulating pads.
2. Description of the Prior Art.
Various types of insulating devices have been developed to maintain a person's comfort when he is in contact with a cold object. In particular, it is known to employ portable cushions for sitting on a tree stump or bleacher seat.
Insulating cushions in the form of polystyrene beads enclosed in a nylon covering are in common use. The polystyrene beads give a comfortable feel and have insulating qualities. However, the beads tend to bunch and shift within the covering; thus the comfort and insulating properties are reduced. The beads also tend to crush into powder with use, thereby reducing the insulating properties. A puncture of the covering permits the beads to fall out, thus destroying the value of the cushion.
U.S. Pat. No. 2,736,030 shows a hinged hunting seat worn folded inside a jacket. The seat is held in place in the jacket by suspender like elastic bands and safety pins. To use the seat the hunter pulls the front of the hinged seat from under the jacket. The seat unfolds to cover his posterior for comfortable sitting. Upon rising, the elastic bands pull the seat into the folded carrying position. The device of the U.S. Pat. No. 2,736,030 is cumbersome to attach to the jacket and is limited to sitting applications.
U.S. Pat. No. 2,738,834 discloses a folding cushion which is designed for mechanical sitting comfort only. The cushion is made of several foam rubber blocks sewn between two outer layers of fabric.
U.S. Pat. No. 3,259,925 teaches a three layered insulating cushion composed of layers of insulating polystyrene, resilient polyepeleyne, and a waterproof flexible material. The three layers are held together with adhesive tape. The layers are enclosed in a fabric casing adapted to enclose two identical cushion halves. The fabric casing is hinged so the two halves fold onto one another for portability. The purpose of the layer of resilient polyester is to make the cushion comfortable to sit on. It is expensive to employ a layer of material in addition to the insulating material merely to create comfort. Further, the materials used in the U.S. Pat. No. 3,259,925 are relatively rigid, and thus the cushion is foldable only along the casing hinges. That construction limits the portability of the cushion as it cannot be carried in a garment pocket but must usually be hand held.
Other illustrations of multi-layer insulated pads include U.S. Pat. No. 2,726,977 for a blanket used primarily in steel mills and U.S. Pat. No. 4,326,310 for an insulated mattress pad. It is apparent that the structures of the U.S. Pat. Nos. 2,726,977 and 4,326,310 render them too bulky for use as personal insulating pads.
Thus, a need exists for an easily transportable personal pad which possesses superior insulating and comfort qualities.